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Is the 5 Second Rule Real?BiologyExperimental Investigation___________________________________________Signature of Sponsoring Teacher___________________________________________Signature of School Science Fair Coordinator TeacherFrank Tiberia640 W. Scott St. Chicago, IL 60610Grade 8Table of ContentsAcknowledgments Page 3Purpose and Hypothesis Page 4Background Research Page 5Materials and Procedure Page 6Results Page 8 Conclusion, Reflection, Application Page 9Reference List Page 12Appendix Page 13AcknowledgmentsI would like to thank my parents for letting me interview them with regards to the 5 second rule and for helping me gather the materials needed for the experiment.Purpose and HypothesisThe purpose of the experiment is to investigate the 5 second rule and see how much if any bacteria will grow in the agar plates after wet food, turkey and dry food, Starburst have been dropped on different floors, a wooden kitchen floor and an outdoor surface, our front steps.My hypothesis is if I drop food and pick it up within 5 seconds, especially indoors, it should be safe to eat initially because it takes a couple hours for bacteria to multiply to a harmful amount.Review of LiteratureBacteria can multiply in as little as 20 minutes, reaching harmful amounts after 1-2 hours in optimal conditions. Bacteria grow best between 40 ° and 140 °F. Bacteria immediately transfers to food on contact.I talked to my family to see if they thought the 5 second rule was real.My mum concluded that you should not eat anything that has been on the floor for even 1 second.My dad said he follows the 5 second rule and sometimes even longer than 5 seconds.Materials and ProcedureMaterialsAgar plates (10)Sterile Swabs (10)Hand SanitizerTurkey (one slice cut into 5 pieces)5 Red StarburstStopwatchCamera (to take photos of the experimental progress)Heat (to give bacteria the optimal chance to grow) ProcedureI. I will prepare my 10 sterile plates containing nutrient agar.II. I will hand sanitize and then will not touch any non-sterile surface.III. I will select two types of “ground.”; Outside my apartment and my kitchen floor.IV. I will drop the first test item, a piece of turkey on the first type of ground.V. I will then start the timer.VI. I will remove the item from the ground after five seconds.VII. I will then swab the item with a sterile swab and make sure I do not touchanything else with the swab.VIII. I will remove the top of the petri dish, keeping the top of the dish in my handaway from any non-sterile surface.IX. I will gently run the swab back and forth in a zig zag pattern on the surface of the agarplate. I will not touch any part of the agar twice.X. I will then put the lid of the petri dish back on and label the dish using the below namingConvention.a. Turkey – Outside – 1b. Starburst – Inside – 2 etc.XI. I will then re-sanitize my hands.XII. I will repeat the same test on the same ground but using a new piece of turkey.XIII. I will perform the test 10 times in total so that I have a good samplinga. 2 x outside with turkeyb. 2 x outside with starburstc. 2 x inside with turkeyd. 2 x inside with starburste. 1 x turkey not been droppedf. 1 x starburst not been droppedXIV. The 2 not been dropped tests will be my controlXV. I will place all the petri dishes together in an environment that is as close to 37º Cas possible (so the bacteria will grow).XVI. I will photograph the plates at the start of the experiment and then at definedintervals of time i.e. after 24 hours, 48 hours, 72 hours, 96 hours, and 120 hours untilbacteria seems to have stopped growing.XVII. I will count the bacterial colonies on each plate at each time point.Controlled VariablesI used Turkey from the same slice of meat and cut it into 5 piecesI used 5 red starburst – to ensure that they were all the same and would not be affected by different ingredients – e.g. food coloringIndependent VariableThis was the ground the items were dropped onto for 5 seconds i.e. indoors or outdoors or not all (the controls)Dependent VariablesThe quantity of bacteria that grewThe types of bacteria that grewResultsAll 10 Agar plates grew bacteria even the control platesOne of the outside Starburst plates only had 2 bacteria at the end of the experiment, I wondered if it was due to the way I swabbed the Starburst or swabbed the agar plate. I noticed several things, as the bacteria were growing condensation formed in small areas on the lid of the agar plate. Even the control plates grew bacteria. It was interesting to see that the indoor plates seemed to grow more bacteria than the outdoor, I was very surprised by that. I also noticed that it seems like different bacteria grow on the foods that were dropped inside compared to outside. The inside bacteria looks a lot like mold whereas the outside seems to have more variety of bacteria.I learned that bacteria grows on food no matter whether it has been dropped on the floor or not. I was surprised that bacteria didn’t grow sooner considering how much bacteria was there after 72 hours there was so much bacteria of many different types by the end of the experiment.Conclusion, Reflection, and ApplicationMy hypothesis can probably be assumed to be correct since the bacteria didn’t really grow until between 24 and 48 hours and by this time you should likely have digested the food and it will no longer be in your body.I know my hypothesis is correct as I counted the bacteria and photographed it and the bacteria wasn’t there until 48 hours later.ReflectionI am confident that the test was fair and conducted in a such a way that the results are accurate. I think that if I repeated it the results would be the same.I would like to re-test using a different indoors surface – maybe the dining room floor instead of the kitchen and using the pavement outside rather than the steps outside our apartment. I feel like the results would still be the same but it might increase the rate that the bacteria grew or the types of bacteria that grew.I am curious to learn more about the bacteria that grew and to see if they are harmful and more importantly how harmful they are. I wonder how sick would they make you?ApplicationThis information can be used to determine if food is safe to eat. It can help you estimate the amount of bacteria on food and allow you to judge if it is safe. This experiment connects to everyone’s life because it investigates food safety, helping people to avoid food poisoning. This information can help in science by helping scientists understand bacterial growth.Reference ListFood Safety Myths Exposed. (2011, June 20). Retrieved November 19, 2017, from, S. (2017, July 18). How Can Bacterial Growth Be Controlled? Retrieved November 19, 2017, from 16, 2015 · by Elizabeth Roebber · in Food Safety. (2017, February 12). Bacterial Growth and Food Safety. Retrieved November 19, 2017, from Scientists Study What to Do If You Drop a Cookie on the Floor. (2014, March 15). Retrieved November 19, 2017, from Wagner, A. B. (2008, November). Food Technology & Processing. Retrieved November 19, 2017, from AppendixData collection sheet

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